A customer of mine ask me to design a PCI board starting from a sample board designed by "Oxford semiconductor". As in many other PCI boards that I designed I followed the PCI specs about traces lenghts ( 1.5 inches for interface data signals and 2.5 +- 0.1 inches for the clock ). Checking the job I discovered that the sample board from OS doesn't follows the PCI specs ( i.e traces more long particularly for high address a26-a31...) Investigating I discovered the same situation in other boards like one from Conexant and Brooktree ( this one designed by Praegitzer Design ) So my question is: Are those boards out of specs or what are the really tollerances about lenghts? best regards Bolis Bortolo BB PCB Design Via Gasparoli, 53 21012 Cassano Magnago ( VA ) - Italy Tel. +39 0331 281457 Fax +39 0331 202794 Email [log in to unmask]